Can you use more than one adapter at the same time using the extra lightning port?

I want to show my students some garageband recording for a music tech. I would normally connect the lightning to vga adapter to my projector but i need a keyboard connected via the lightning to usb cable.
As the vga adapter has a lightning port, is it possible to put the lightning to usb adapter into the vga adapter so i can use a midi keyboard and show what I am doing via the projector at the same time?
Or does that port only allow for charging the device?